The main goals of our research program are to advance our understanding of the social phenotype of Williams syndrome (WS), and to define the cognitive mechanisms that underlie the unique social-affective features that define this neurodevelopmental disorder. Our current studies have demonstrated that adolescents and adults with WS are better than age and IQ matched learning disabled/mentally retarded controls oh standardized measures of face recognition, and in their ability to interpret prosodic cues to speakers' emotions in filtered speech, performing at similar levels to normal controls on these tasks. Moreover, they are more likely to notice subtle changes to social aspects of complex scenes, respond more empathically toward a person in distress, and on psychophysiological measures of arousal, appear to find social-affective stimuli less threatening than other people. In the next award period we plan to continue this line of research addressing the following questions: (1) Do people with WS show the same developmental changes during the early adolescent stage in face recognition as do controls? (2) Do people with WS interpret eye gaze information in the same way as controls? (3) Do people with WS show greater sensitivity to affective information in faces compared to controls using implicit tasks? (4) Do people with WS attend more than controls to social information in dynamic scenes, as evidenced by eye-tracking data? (5) Do people with WS find social stimuli differentially more rewarding than controls? (6) Do people with WS find social-affective stimuli less threatening, as evidenced by psychophysiological measures of arousal, than controls? We plan to investigate these questions in a series of experiments comparing adolescents and young adults with WS to age/IQ matched and normal age-matched controls, and predict that experiments addressing questions (1) - (2) will find comparable patterns of performance in the WS and control participants. In contrast, experiment addressing questions (3) - (6) will highlight unique performance patterns in WS, reflecting their greater attention and singular affective response to social information. This research program will not only advance our understanding of WS; it has the potential to influence developing theoretical models in the growing field of social cognitive neuroscience. [unreadable] [unreadable] [unreadable]